Martial law in the United States refers to times in United States history in which in a region, state, city, or the whole United States was placed under the control of a military body. On a national level, both the US President and the US Congress have the power, within certain constraints, to impose martial law since both can be in charge of the militia. In each state, the governor has the power to impose martial law within the borders of the state. In the United States, martial law has been used in a limited number of circumstances, such as New Orleans during the Battle of New Orleans; after major disasters, such as the Great Chicago Fire of 1871, the 1906 San Francisco earthquake, or during riots, such as the Omaha race riot of 1919 or the 1920 Lexington riots; local leaders declared ma